An IP address is a numeric address.
It's an identifier for a computer or device on a network. Every device has to
have an IP address for communication purposes. The IP address consists of two
parts. The first part is the network address and the second part is the host
address. There are also two types of IP addresses. The first one is the most
common one, it's called IP version 4 and a second type is IP version 6. IP version
4 is the current version of IP addresses. It's a 32-bit numeric address written as
four numbers separated by periods. Each group of numbers that are separated by
periods is called an octet. The number range in each octet is 0 to 255. This
address version can produce over 4 billion unique addresses. In the world of computers and networks
this IP address in this format here is meaningless. Computers and networks don't
read IP addresses in this standard numeric format and that's because they
only understand numbers in a binary format. A binary format is a number that
only uses 1s and 0s The binary number for this IP address is this
number shown here. This binary number is what computers and networking devices
actually read. So the question is, how do we get this binary number from this IP
address? IP address 4 is made up of four sets of
eight binary bits. And these sets are called octets. The bits in each octet are
represented by a number. So starting from the left, the first bit has a value of
128 then 64 then 32 and so on. All the way down to 1. Each bit on the octet
can be either a 1 or a 0. If the number is a 1 then the number that it
represents counts. If the number is a 0 then the number that it represents
does not count. So by manipulating the 1s and the 0s in
the octet, you can come up with a range from 0 to 255. So for example the first
octet in this IP address is 66. So how do we get a binary number out of 66?
First you look at the octet chart and you would put 1s under the numbers
that would add up to the total of 66. So you would put a 1 in the 64 slot. So now
you already have 64, so we need 2 more. So let's put in number 1 in the two slot. So
now if we count all the numbers that we have 1s underneath them, you will get a
total of 66. All of the other bits would be 0s because we don't need to count
them since we already have our number. So this number here is the binary bit
version of 66. So we'll put that number down here So let's do the next number which is 94.
So let's put a 1 under 64, 16, 8, 4, & 2. So if we were to add all the numbers that
we have 1s underneath them, we would get a total of 94. And since we don't
want to count any of the other numbers we just put 0s under the rest. So the next number is 29. So let's put a
1 under 16, 8, 4, & 1. And when you add all the numbers up you get 29. And our last number is 13. So let's
select 8, 4, and 1. And when you add those up you get 13 When the internet was first developed,
programmers didn't realize how big it would become. They thought that IP version
4, which produced over 4 billion addresses, would be enough. But they were
wrong. IP version 6 is the next generation of IP addresses. The main
difference between IP version 4 and IP version 6 is the length of the address.
The IP version 4 address is a 32-bit numeric address.
Whereas IP version 6 is a 128 bit hexadecimal address.
Hexadecimal uses both numbers and alphabets in the address. So with this
type of address, IP version 6 can produce an unbelievable 340 undecillion IP
addresses. That's the number 340 with 36 digits after it. So as you might have
guessed, IP version 6 is more than enough for the foreseeable future So as stated before, IP version 6 is a
128 bit hexadecimal address. It's made up of 8 sets of 16 bits with the 8 sets
separated by colons as you can see here. So in a similar way that we converted an
IP version 4 address to a binary number, this is how we convert a binary number
to a hexadecimal address. In an IP version 6 IP address each hexadecimal
character represents 4 bits. So we have to convert 4 bits at a time to get one
hexadecimal character. So starting from the beginning, we convert the first 4
bits and put those bits up there against our 4-bit chart which includes an 8, 4, 2,
and a 1. So if we count the numbers that we have 1s underneath them, you wind up
with a 2. So a '2' is the first hexadecimal character
in this IP version 6 address. So let's do the next four bits and put
those under our four bit chart So if we count all the numbers that we have
1s underneath them, we have a '4' and a '2' and if we add those up we get 6. So a '6'
is the second hexadecimal character in this IP address So let's do our next set of 4 bits.
And if we add all the numbers that we have 1s underneath them, we get a total
of 13. But the problem is since 13 is a double-digit number, we
cannot use a double-digit number to represent 4 bits. And that's because
in a hexadecimal format, double-digit numbers have to be represented with a
single alphabet which is 'A' through 'F'. So in this case we have to use another
chart for any 4 bits that the sum is 10 or higher. So in this chart up here, if
the sum was 10, then we would use the letter 'A'. Or if the sum was 11, then we
would use a 'B'. But in this case our sum is 13. So now for the third character in
our binary number we would put a 'D' So in our last example let's do the
fourth set of bits. And if we add those up we get 11. So we have a double-digit
character again which means that we have to convert it to a single character
alphabet. So if we look at our chart up here, 11 converts to a 'B'.
So the first 16 bits of this binary IP version 6 address, converts to the
hexadecimal address as 26DB.
